<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Title</title>
	<style>
		[v-cloak] {
			display: none;
		}
	</style>
</head>
<body>

<div id="app">
	<template>
		{{ message1 }}
	</template>
	<br>
	<div v-cloak>
		{{ message2 }}
	</div>
</div>

<script src="https://cdn.bootcdn.net/ajax/libs/vue/2.6.9/vue.js"></script>
<script>
  let app = new Vue({
    el: '#app',
    data: {
      message1: 'aaa',
      message2: 'bbb'
    }
  })

</script>
</body>
</html>